Heat olive oil over medium heat.
Add leek and a pinch of salt. Saute until translucent.
Add the fennel and sauce about 3 more minutes.
Stir in garlic, asparagus and salt.
Pour in 1 cup of stock, cover and cook 3-5 minutes. Remove from heat.
Add remaining stock. Take half of soup and place in blender. Puree until smooth.
Stir in the pepper, parsley, dill, lemon juice, lemon zest and 1/4 tsp salt.
Serve warm.